Daikoku Shusaku, Ako Takuro, Kato Rumiko, Ohtsuka Isao, Kanie Osamu
Mitsubishi Kagaku Institute of Life Sciences (MITILS), Machida-shi, Tokyo, Japan.
J Am Soc Mass Spectrom. 2007 Oct;18(10):1873-9. doi: 10.1016/j.jasms.2007.07.021. Epub 2007 Jul 29.
Glycans, a family of compounds often attached to proteins and ceramides, are diverse molecules involved in a wide range of biological functions. Their structural analysis is necessary and is often carried out at the microscale level. Methods based on mass spectrometry are therefore used, although they do not provide information regarding isomeric structures often found in glycan structures. If one finds "factors" characteristic of a certain isomer, this information can be used to elucidate an unknown oligosaccharide sequence. One potential technique is to use energy-resolved mass spectrometry (ERMS) that has been used to distinguish a pair of isomeric compounds. Thus, compounds in a combinatorial library might be effectively used for this purpose. We analyzed a set of 16 isomeric disaccharides, the structures of which consisted of all possible combinations of anomeric configurations and interglycosidic linkage positions. All of the compounds were distinguished based on ERMS where normal collision-induced dissociation could distinguish only seven compounds. Furthermore, it was shown that alpha-glycosidic linkages of fucose were more reactive than the beta-isomers and the secondary glycosides were more reactive than the primary glycosides.
聚糖是一类常与蛋白质和神经酰胺相连的化合物，是参与多种生物学功能的多样化分子。对其进行结构分析很有必要，且通常在微观层面开展。因此会使用基于质谱的方法，不过这些方法无法提供有关聚糖结构中常见的异构体结构的信息。如果发现某种异构体的“特征因素”，该信息可用于阐明未知的寡糖序列。一种潜在技术是使用能量分辨质谱（ERMS），它已被用于区分一对异构体化合物。因此，组合库中的化合物可能有效地用于此目的。我们分析了一组16种异构二糖，其结构由异头构型和糖苷键连接位置的所有可能组合构成。基于ERMS可区分所有这些化合物，而常规碰撞诱导解离只能区分其中7种化合物。此外，结果表明岩藻糖的α-糖苷键比β-异构体更具反应性，二级糖苷比一级糖苷更具反应性。
